What happens if you don’t sleep for 24 hours? You’re basically drunk

For college students, new parents and employees dogged by deadlines, the all-nighter is nothing new.

But going without sleep leaves you basically drunk, putting you at the equivalent of a .1% blood alcohol content as you drive to work, make decisions and interact with others.

“The first thing that goes is your ability to think,” said Joseph Ojile, M.D., a board member with the National Sleep Foundation and founder of Clayton Sleep Institute in St. Louis. Judgement, memory and concentration all suffer impairment by the body’s 17th hour without sleep, he said.

Coordination deteriorates as well in those intervening hours, said Ojile, a professor at Saint Louis University School of Medicine. Irritability sets in, too. Pain becomes more acute and the immune system suffers, he said, leaving the body more open to infection.

“Here’s the worst part about the lack of judgement,” Ojile said. “The person is unaware of their impairment. How scary is that? ‘I’m fine, I’ll just drive home. I’ll do my work at the nuclear plant, no problem. Or fly the plane, no problem.’”

It’s not entirely clear how the effects worsen past 24 hours, Ojile said, other than they do. The brain starts shutting down in trance-like microsleeps, 15- to 30-second spells that occur without the person noticing. Eventually, not sleeping results in death.

“It could range in people, but it could be a week or two weeks,” he said. “If you want to kill someone eventually, you just keep them up.”

Drowsy driving caused 72,000 crashes and 800 deaths from 2009 to 2013, according to a report from the National Highway Traffic Safety Administration. Nearly one-third of all drivers admitted to driving drowsy within the previous month in a 2015 AAA poll.

If you find yourself on the road and short on sleep, don’t think you can simply chug a cup of coffee and hit the road. It takes an hour for caffeine to kick in, Ojile said, so pull over for a bit and take break. You could use the rest.